Sietings preventer eos stokers



Oct. 23, 1928.

A. E. WEINGARTNER SIFTINGS PREVENTER FOR STOKERS 4 Sheets-Sheet Original Fi e 2 1924 Oct. 23, 1928. 1,689,092

A. E. WEINGARTNER SIFTINGS PREVENTER FOR STOKE-RS Originai Filed Jan. 21, 192 4 s t s 2 Oct. 23, 1928.

1,689,092 A. E. WEINGARTNER SIFTINGS PREVENTER FOR STOKERS Original Filed Jan. 21, 1924 .4 Sheets-Sheet 4 Sheets-Sheet 4 A. E. WEINGARTNER SIFTINGS PREVENTER FOR STOKERS Original Filed Jan. 21, 1924 Oct. 23, 1928.

Patented Get. 235, 1928 Ul'lE ATEF ANTHONY E. XVEING-AIi-TNER, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR T AMERICAN ENGINEERING COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A COR- PORATION OF PENNSYLVANIA.

SIFTINGS PREVENTER FOR STOKERS.

Application filed January 21, 1924, Serial No. 687,534.

My invention relates to st-olrers, having particular relation to automatic stol: rs of the underfeed type.

One object of my invention is to provide apparatus of the class described which includes a novel form of pusher, whereby the green coal may be progressively and positively moved from the retorts up over the tuyere plates.

In practice, the pusher mechanism is usu ally made and assembled without machined fittings in order to prevent the cost of the stoker equipment from becoming prohibitive. As a result, the more or less loose fit bet-ween the pushers and the guides permits the escape of considerable quantities of the green coal as siftings. The accumulation of the siftings over a relatively shortperiod of time is so great that it must be frequently removed not only to avoid the clogging of the working stokerparts but also to avoid danger from fir Another object of my invention, therefore, is to provide simple and inexpensive means for substantially avoiding the continued escape of the green coal between the relatively movable parts of the stolrer mechanism.

A further object of my invention is to provide pusher apparatus, wherein the siftings tending to work between the moving parts of the pusher constitute the sealing material. and wherein the eflicacy of the seal thus formed increases with the length of service of the stoker.

VVit-h these and other objects and applications in mind, my invention further consists in the details of construction and operation and arrangement hereinafter described and claimed and illustrated in the accompanying drawings, wherein Fig.1 is a vertical, sectional view of the front portion of an inclined, underfeeo stoker embodying my invention;

Fig. 2 is a perspective view of one of the pushers of Fig. 1;

Fig. 3 is a perspective view of one of the two sealing members which is designed to be detachably mounted on the structure of Fig. 2;

Fig. l is a similar view of an extension member for the structure of Fig. 2;

Fig. 5 is a similar view of one of the two sealing members designed to be detachably mounted on the structure of Fig. 1;

Renewed June 22, 1928.

Fig. 6 is a side elevational view of the structures of Figs. 2 to 5, inclusive, in their as sembled position;

Fig. 7 is a top-plan view of the structure of Fig. 6; and

Fig. 8 is a detail, transverse sectional view taken on the line V III-VIII of Fig. 1.

In the illustrated form of embodiment of my invention shown in Fig. 1 of the drawings, I provide an inclined, automatic stoker 1 of the under-feed type which has its upper end carried by a front wall 2 and its lower end supported by a beam 8 of the main supporting frame. The Stoker 1 may comprise a plurality of series of inclined tuyeres 1, each series extending from a fuel supply opening 5 in the front wall 2 to a lower grate plate (5 which is supported on a movable structure carried by the main supporting beam A series of retorts 7, which respectively alternate with the series of tuyeres l, are pro vided with a common inclined base section 8. The latter is slidably mounted on rails 9 and 11 carried by side tuyere supporting plates 12 and 13, respectively, all as will appear more fully hereinafter. The tuyere supporting plates 12 and 13 have their upper ends mounted upon the front wall 2 and their lower ends on the main beam 3. Each tuyere supporting plate may comprise two sections 14 and 15 which are secured together to form a single supporting element, as shown in Fig. 1.

The stoker 1 may be supplied with material to be burned, say green coal, from a hopper 16 which opens into a cylinder 17 having an operative connection with the inlet opening 5 in the front wall 2. The continuous passage of the green coal from the hopper 16 in through the furnace opening 5 and down into the retorts 7 may be effected by means of a piston 18 which is slidably mounted in the cylinder 17. The piston 18 is operatively associated by means of a connecting rod 19 with a driving crank 20, which may be driven by power apparatus 21 of the usual type.

The inclined floor section 8 of each retort 7, which extends from the fuel inlet opening 5 to the grate plate 6, may be reciprocated by means of a pusher rod 22 which has an inner end secured to the movable floor 8 and an outer end slidably mounted in a flanged head portion 23 of the cylinder 17. The outer end of the pusher rod 22 is provided with a threaded boring 2st for the reception of a corres-ipomlingly threaded end portion of a rod of reduced diameter with respect to the pusher rod 22. The piston 18 is provided with an extension 26 which is per torated to receive slidably the extension rod 25. On the outer end ot the rod 25 is suitably mounted an adjustable stop Vhen the piston extension 26 is reciprocated under the action of the crank 20 and connecting rod 19, the outer end oi the pusher rod 22 and the adjustable stop 29 are snc cessively engaged and moved an amount depending upon the position of the adjustable stop 28. Hence, it ran be seen that while the piston 18 may have a stroke of, say, nine inches, the stop 28 may be so adjustrnl as to vary the stroke of the movable door 8 from zero to that of said piston 18.

Referring more particularly to the construction of the movable floor 8, as shown in Figs. 2 to 8, inclusive, the same comprises a plurality of pushers 29 arranged in stepped relation, each pusiier comprising a longitud nally extending member having substantially horizontal and inclined, front and rear top surtaces 31 and 32, respectively. Side surfaces and 34 of each pusher are pro vidcd with grooves 85 anc 36 adapted to receive slidably the guide rails 9 and 11, respectively, whereby the weight of each pusher may be individually supported upon its own guide rails.

Each pusher 29 is further provided with spaced recesses 37 and 38 6) opening into the base of the same, forming an intermediate wall 39 and a front end wall 4-0. In assembling the several pusher-s 29 to form the movable floor 8, the rear end of one pusuer is mounted on the horizontal front surface 31 of: the next pusher and the two are rigidly secured together by means of a plate 41 which is bolted to the end wall 10 of? the lower pusher and to the intermediate wall 39 of the upper pusher.

A topmost pusher 42 is provided with an extension 43 (Fig. having a top surface it and side surfaces and 46, the latter being provided with grooves 47 and continuous with the grooves and 36, respectively. The extension 43 also has rear and front end surfaces 4-9 and 51, respectively, the former being secured to the front end wall of the pusher 42 by means of bolts 52. The bolts 52 may also serve to secure a connecting member 53 to the front end surface 51 of the extension 18. The connecting member 53 is also rigidly secured to the inner end of the pusher rod 22.

As previously pointed out, experience has shown that as the several. pnshers 29 are moved back and forth intermediate the tuyere supporting plates 12 and 13', a considerable amount of the coal 54 (Fig. 8) being operated on sitts between said tuyere supporting plates and said pushers and these sittings must be removed from time to time from under the stoher 1 in order to avoid the so-called sealing up of the stoker and the danger from tire. To this end, I provide a seal, wherein the escaping coal dust is the permanent filler.

The seal is formed by providing the upper corners and 56 of each, pusher 29 with longitudinally extending grooves 57 and 58, respectively, adapted to receive sealing member or liners 59 and 60. Each groove comprises an inclined wall 61 (Figs. 2 and 8) and a horizontal base portion. 62. The several sealing members are loosely mounted in said grooved corners, the extent of lateral moven'ient therein being determined by the walls 61 and the adjacent tuyere supporting plates and 13. The lateral movement, however, is sutlicient to permit a certain port on of the green coal o l to work in between the side walls 61 and the adjacent sides of the sealing members 59 and 60, whereby a we .ig action may obtain, wherein the opposite sides of the sealing members 59 and 60 are c used to engage frictionally the tuyere supporting plates 12 and 13. Such sittings as may work in between the sealing members and 60 and the tuyere supportiug plates 12 and 13, when the pushers 39 are first actuated, are not held in this position but falls through to the underside of the slolzer 1. Thema i ial. entering the space between the ser iling members 59 and 60 and the valls 61, however, is caused to accuu'mlate by reason of the horizontally extending base portions 62 of the corner reces es and 56, wherein the sittings move in a horizontal direction as they tend to Work between the moving parts. Experience has shown, however, that the accumulating si'it ii'igs soon pack in this horizontal portion of the L-shaped seal, thereby preventing the further escape of the coal.

The sealing members 59 and may be loosely locked in position by means of lugs 63 andv 6-1 which are respectively secured to the rear and front portions thereof. Each rear lug 68 comprises a depending portion (35, which extends trom the base of the sealing member, a laterally extending portion 66, which extends from the upper portion of the lug (i3, and a longitudinally extending porti -.1 til, which extends from the base portion Of the depending portion 65. Each side of the pusher is provided with corresponding vertical, lateral and longitudinally extending recesses (38, G9 and 71, respectively, which are adapted to receive the lug portions just described.

The vertical lug portion 65 extending into the depending recess 68 avoids longitudinal movement of he liner. The longitudinally extending portion 67, extending into the adjacent recess 71, prevents vertical movement beyond a predeterminedv extent. The lateral portion 66, extending into the recess 69 prevents the escape of sittings between the vertical locking portion and the adjacent side wall of the recess 68. The lateral extension 66 also serves to avoid vertical movement of the scaling member beyond an extent sufficient to permit the siftings to work in between the base of the sealing member and the horizontal base portion 62. Lateral movement of the sealing member away from the wall 61 is limited by engagement with the adjacent tuyere supporting plate, as above set forth.

The front locking lug 6% is similar in design to the rear locking lug 63 with the exception that a longitudinally extending portion '72 thereof projects toward the rear end of the sealing member, whereas the corre sponding extension 67 of the lug 65 extends toward the front end of said liner. The extension 43 is provided with sealing members 73 having locking lugs 7 4t and at the opposite ends thereof as in the case of the sealing members 59 and 60. The construction of the extension 43 is otherwise as above indicated in the description of the pusher construction.

In operation, as coal is fed from the hopper 16 intothe cylinder 17, the piston 18 operates to feed positively said coal through the stoker opening 5 down into the stoker retorts 7. The reciprocation of the piston 18 through the pusher rod 22 causes a limited reciprocation of the retort fioorstructure 8, whereby the green coal is gradually and continuously forced out of the retorts 7 up onto the tuyeres 4, as will be readily understood by those skilled in the art.

The reciprocation of the several pusher 29, constituting the retort floor 8, causes a certain amount of the green coal to work in between the sealing members 59 and 60 and the adjacent walls 61 of the recessed corners 55 and 56. This sifting of material continues until the coal has worked in between the base of the sealing members 59 and 60 and the horizontal portion 62 of the upper corner grooves where the sifting material tends to pack, thereby preventing the further escape of sittings. Experience has shown that the seal thus formed becomes more effective as the pusher continues in service. As above noted, the sitting of the material between the adjacent vertical sides of the sealing members 59 and 60 and the pushers, operates to force the liners into frictional engagement with the adjacent surfaces of the tuyere supporting plates, thereby preventing coal from sitting between these surfaces.

l/Vhile I have shown only one embodiment of my invent-ion, for the purpose of describing the same and illustrating its principles of construction and operation, it is apparent that various changes and modifications may be'made therein without departing from the spirit and scope of my invention. I desire, therefore, that only such limitations shall be imposed thereon, as are indicated in the ap pended claims or as are demanded by the prior art.

I claim:

1. in a device of the class described, the combination with a pair of spaced supporting members provided with guide rails, of a pusher slidably mounted on said guide rails. the sides of said pusher adjacent to said members being provided with longitudinally extending recesses, and sealing members so loosely positioned in said recesses as to permit material to work in between said sealing members and said pusher to form a seal.

2. In a device of the class described, the combination with a pair of spaced supporting members provided with guide rails, of a pusher slidably mounted on said guide rails, the sides of said pusher adjacent to said members being provided with longitudinally extending recesses, and sealing members loosely mounted in said recesses, said sealing members being provided with locking lugs preventing longitudinal and vertical displacement beyond a predetermined extent.

In combination, a pusher having a top surface and grooved side surfaces, and a sealing member in each side groove provided with locking lugs preventing longitudinal and vertical displacement beyond a predetermined extent.

4. In combination, a pusher having a top surface, recessed side surfaces and grooved upper corners extending lengthwise of said pusher, and sealing members positioned in said grooved corners, said members being provided with locking lugs extending into the recesses in said side surfaces, whereby longitudinal and vertical displacement of said sealing members beyond a predetermined degree is prevented.

5. In combination. a pusher having a top surface, recessed side surfaces, and grooved upper corners extending lengthwise of said pusher, and sealing members positioned in said grooved corners, said members being provided with looking lugs extending into the recesses in said side surfaces, said locking lugs comprising vertical, lateral and longitudinally extending portions.

6. In combination. a pusher having a top surface, grooved u pper corners extending lengthwise of said pusher and recessed side portions, each recess comprising a vertical portion extending from said groove. a lateral portion extending from said vertical portion and a longitudinal portion also extending from said vertical portion, and sealing members loosely positioned in said grooves said members having locking lugs so formed as to extend into said recesses.

7. In combination, a pusher having a top surface, grooved upper corners extending ill) .iengthwil ie of said pusher and recessed side portions, each recess comprising interconnected vertical, lateral and longitudinally extending portions, and sealing members loosely positioned in said grooved corners, said members having locking lugs,- each lug comorising vertical, lateral and longitudinally extending portions movable into said recesses.

8. In combination, a pusher having a top surface and grooved side surfaces, sealing members loosely positioned in said grooves and provided with locking lugs, and a pair of spaced plates providing a slidable mounting for said pusher, the mounting of said members on said pusher being such that a part oil? the material to be operated on by said pusher works in between said members and pusher forming a seal, the members being forced into engagement with said plates by the wedging action of the sealing material.

9. In a device of the class described, spaced plates, a pusher slidably mounted on said spaced plates and provided with grooves extending lengthwise of said pusher, and sittings preventing means comprising sealing members positioned in said grooves and locked to said pusher, the members being movable into engagement with said plates as the iaterial to be operated on works in between said members and said pusher.

10. In. a device of the class described, a pusher having a top surface, recessed side surfaces and grooves extending lengthwise of the pusher, spaced plates provided with rails extending into said recessed side surfaces, and sealing members loosely positioned in saidgrooves and locked to said pusher, the members being movable into engagement with said plates as the material to be operated on works in between said members and said pusher.

11. Stoker apparatus comprising a pusher, a pair of supporting members therefor, said pusher. being provided with longitudinally extending recesses, and sealing; members loosely mounted in said recesses, said sealing members being provided with looking lugs preventing longitudinal movement beyond a n'edetcrmned extent.

12. Stoker apparatus comprising a pusher having a detachable extension, corresponding sides of said pusher and extension being grooved, and sealing" means positioned in said grooves and. provided with locking lugs adapted to cooperate with said pusher and extension.

13. A pusher having a groove extending lengthwise thereof and also a. recessed port-ion depending from said groove, and a sealing member loosely positioned in said groove and provided with a lug disposed in said recess, said lug tending to prevent the escape of siftingrs through said recess.

let. In a stoker, the combination with. a pair of spaced supporting members, of a pusher slidably mounted thereon, the sides of said pusher adjacent to said members being provided. with recesses, and sealing members loosely mounted in said recesses, said sealing members being provided with locking lugs preventing a vertical displacement beyond a predetermined extent.

ANTHONY E. EINGARTNER. 

